1. Field of the Invention
The invention relates to a pipe arrangement with a pipe and a pipe coupling. The pipe coupling has on a front face a peripheral groove with a groove bottom. The pipe is inserted into the peripheral groove and welded with the pipe coupling.
2. Discussion of Background Information
A pipe arrangement of the type generally described above is widespread, particularly in vehicle manufacturing. For example, the pipe is used to transport a fuel from a fuel container to a fuel consumer, e.g., an injection pump supplying an internal combustion engine. To facilitate the assembly, as well as later repairs, the pipe is connected to a pipe coupling firmly and, as a rule, permanently. The pipe coupling can then come into engagement with a corresponding pipe connection, in the cited example, on the tank or on the injection pump. To this end the pipe connection is often inserted into the pipe coupling and snapped there.
In order to produce the connection between the pipe and the pipe coupling, the pipe is inserted into the groove on the front face of the pipe coupling and welded there. For welding, so-called friction welding is often used, in which the pipe coupling is rotated in the groove with respect to the pipe. The frictional heat thereby produced melts the material of the pipe and/or the pipe coupling so that a connection by adhesive force between the pipe and the pipe coupling results.
However, it has been established that in some cases the quality of the welded joint between the pipe and the pipe coupling is not adequate. This often cannot be detected immediately after the production of the pipe arrangement, but is shown only after a certain operating period. Under unfavorable circumstances it can be observed that the fluid flowing through the pipe arrangement leaks out between the pipe coupling and the pipe, which is not admissible in many cases.